Sir Alex Ferguson says he is not surprised by Manchester City's flying start to the season, and admits United's rivals have "changed football" with their spending power.

Despite dropping just two points in their opening seven Premier League games, and scoring 24 goals in the process, Manchester United go into the current international break with only a single goal advantage over City, who have also drawn just once.

It has heightened anticipation for the first derby clash of the season, at Old Trafford on 23 October, although Ferguson insists the Blues' fast start has not caught him by surprise.

"I've said all along that would happen," Ferguson told Inside United. "They are a good team and they were always going to be there or thereabouts.

"Sergio Agüero was bound to do well, coming into the Premier League, because he is such a goal threat around the penalty box. David Silva is also a very good player. We just have to make sure we are ready for City when we meet them."

"The impetus City now have – they have a huge squad of players and the financial power to attract some of the best footballers in the world – actually changes the focus of the derby these days," said Ferguson.

"The talking point isn't so much the actual game but the dynamics of how Manchester City have changed football and what we do to compete with that."

Yet, ahead of that game, United must visit Anfield to face the team they deposed as England's most successful club in May when they secured a record 19th league title. Liverpool have been difficult opponents to overcome in recent seasons, though, with Dirk Kuyt scoring a hat-trick in last season's corresponding fixture.

"We have been poor there of late," said Ferguson. "On a couple of occasions we have been outfought by them, which is disappointing. The atmosphere plays a part. Every time we go there it is as if it's the biggest game of the century."